There is another thing to consider here...I'm assuming you're more attracted to larger dog breeds because they're more imposing?
What happens if out when hiking your dog slips and injures one or two of its legs? You'll need to be able to carry your dog alone all the way back before being able to seek veterinary care.
I would also suggest a Rottweiler. They're soppy with those they know, don't care where they are as long as they're touching you (slept with mine in a small 2 man tent a few times) and they love walking. Even when they're highly socialised, they take at least 10 mins to evaluate strangers, they like to make eye contact, and due to their reputation from films & media, most people tend not to chance it. Incredibly trainable, they're so obsessed with you eager to please they try working out what you want so meet you half way with training. Mine would watch every little movement I made and would move accordingly so he was rarely 'in the way', similarly 50% of his judgment of strangers was made from my judgement, he'd keep looking at my expression/reaction/interaction.
That said, I wouldn't want to carry one very far. They're mainly black so can overheat. They're prone to separation anxiety and like most pedigree breeds can suffer with other health issues.
Also another aspect. Until you get that bond with your dog, a dog is just a dog, but after, as much as my dog did protect me, I became worried about him actually biting someone because at least, in the U.K. even if someone is burgling your home and your dog bites them, your dog is considered 'dangerous' and likely then destroyed, and on top of that you can be prosecuted.
Even worse, it is also an offence for your dog to worry people or if they believe your dog will harm them, it's treated as severely as if they had. And I'm sure it wouldn't surprise you to learn that people will cause a scene because your 'reputation' dog glanced at them part way through sniffing and peeing in a bush.
Many other dog owners won't be happy/trust your dog around theirs, even if yours is 100% under your control and theirs is a delinquent. Same with some people with children.
Also, 'reputation' dogs sadly are still used for fighting or for training a fighting dog, and therefore stolen for this reason, from outside shops, people's gardens/homes/cars.
A 'reputation' dog can also leave you isolated, people will cross a road to stay away from you.
If you pop into a shop, tie your dog outside...children don't understand reputation until older and will just see a dog they want to touch. Your dog doesn't see a child, just a short human harassing them. Even if your dog doesn't mind this, the parents then sometimes cause a scene.
Most people don't ask to touch your dog, they just do, and in dog society it's rude to touch before you know someone, depending on where and how the touch happens, it can also be a threat to the dog.
The practicalities of wanting a 'scary looking dog' with wanting to socialise with other camping people are a little juxtaposed and may not achieve your desired outcome.
Consider, your new friend wants to rob you. Your dog knows them as 'friend' and may not react.
Consider your new friend is drunk and wants to fuss your dog late or someone mistakes your van for theirs and your dog bites them.
Consider someone has entered your van, dog has gone straight for the throat and killed them. You were asleep, the intent of the intruder wasn't obvious...
There's a lot to consider, your dog's behaviour will likely be different with/without you around.
Your vision may pan out how you envision it, but you have to be aware that for that to happen you will need to meticulously plan and research and work hard to train and fully know your dog, even then, luck must be on your side.
Apologies for the length of the post and GL on your travels OP 